High risk of a major tornado outbreak today; 13 dead from Leap Day outbreak

A powerful spring storm system is gathering strength over Missouri this morning, and will track northeastward into Southern Michigan tonight. The atmosphere in the storm's warm sector, south of the the warm front and east of the cold front, is very unstable, thanks to a flow of warm, moist air from the Gulf of Mexico at the surface, and very cold, dry air aloft. A powerful jet stream with winds winds aloft blowing at 150 mph will interact with this unstable air, and the strong change of wind speed and direction with height (wind shear) associated with this jet will impart a strong twisting motion to updrafts that from in this afternoon's thunderstorms along the cold front. These are ideal conditions for tornado formation, and a large tornado outbreak with damaging long-track tornadoes is likely late this afternoon in the Ohio and Tennessee Valleys. NOAA's Storm Prediction Center has placed Central Kentucky, Northern Tennessee, and a small portion of Southern Indiana in their "High Risk" area for severe weather Friday afternoon and evening, and is warning of the possibility of long-track significant tornadoes. While the conditions are not as dangerous as those we saw in 2011 during the May 21 - 25 Joplin, Missouri and late April Southeast U.S. tornado outbreaks, the potential exists for a punishing tornado assault with many more strong and violent tornadoes than occurred during the Leap Day outbreak. A number of severe thunderstorms with damaging winds have already formed this morning along the storm's warm front, in Missouri, Indiana, and Illinois. Consult our Severe Weather Page and Interactive Tornado Page to follow the storms.

Figure 1. NOAA's Storm Prediction Center has placed Central Kentucky, Northern Tennessee, and a small portion of Southern Indiana in their "High Risk" area for severe weather Friday afternoon. This is highest level of alert.

Figure 2.NOAA's Storm Prediction Center is calling for a 30% chance of tornadoes today within 25 miles of each point in the pink shaded area. Within the hatched area, there is a 10% or greater probability of strong EF-2 and EF-3 tornadoes, or violent EF-4 and EF-5 tornadoes within 25 miles of a point.

Leap Day tornado outbreak death toll hits 13The cleanup continues today from the round of deadly tornadoes that pounded the Midwest on Leap Day, killing thirteen people. The outbreak began on February 28, when nine confirmed tornadoes touched down. A pair of EF-2 tornadoes hit Buffalo, Missouri and Harveyville, Kansas, with each twister causing one death. Also on that day, a weak EF-0 tornado moved over open fields near Gandy, Nebraska--the first February tornado in Nebraska since record keeping began in 1950. The outbreak continued on Leap Day, February 29, with 27 more confirmed tornadoes. Hardest hit was Harrisburg, Illinois, where a violent EF-4 tornado with 180 mph killed six, injured approximately 100, and damaged 200 homes and 25 businesses. The tornado cut a path 26.5 miles long and 275 yards wide across the town, according to the NWS damage survey. The only EF-3 tornado of the outbreak hit Asherville, Missouri that day, killing one person. The other deadly tornadoes of the outbreak included an EF-2 tornado that killed one person in Cassville, MO; an EF-2 that killed two in Monterey, Tennessee, and an EF-1 that killed one person in Smithville, Tennessee. An EF-2 tornado also plowed through downtown Branson, Missouri on Leap Day, injuring 33 people. An NWS storm survey found the tornado was 400 yards wide and carved a path 22 miles long. Overall, damage from the two-day tornado outbreak will run in the hundreds of millions, and could add up to the first billion-dollar weather disaster of 2012 in the U.S. The 36 confirmed tornadoes from the outbreak make it the second largest February tornado outbreak since record keeping began in 1950. The biggest February tornado outbreak occurred on February 5 - 6, 2008, when 92 tornadoes touched down.

Figure 3. Damage at the Branson, Missouri Hilton after the Leap Day tornado. The tornado blew out or cracked windows in 219 of the hotel rooms in the 12-story/295 room Hilton Branson Convention Center, and extensively damaged three of Branson’s 50 plus theatres--Americana Theater, Branson Variety Theater and Dick Clarks’ American Bandstand Theater. Image credit: BransonRecovery Facebook page.

Portlight disaster relief charity responds to the Harrisburg, Illinois tornadoPortlight has a seasoned veteran from last year's tornado recovery efforts in Harrisburg, IL, and is looking for more people to volunteer their time. They are teaming with another disaster recovery charity, Team Rubicon, in the effort. As usual, they will be focusing efforts on the unserved, under served and forgotten. Please visit the Portlight Disaster Relief blog to learn more. Donations are always welcome!

Figure 4. Team Rubicon at work during last year's tornado recovery efforts.

Portlight has a seasoned veteran from last year's tornado recovery efforts in Harrisburg, IL, and is looking for more people to volunteer their time. They are teaming with another disaster recovery charity, Team Rubicon, in the effort. As usual, they will be focusing efforts on the unserved, under served and forgotten. Please visit the Portlight Disaster Relief blog to learn more.

West Liberty has reported Catastrophic damage reported in the area after a direct hit by an extremely intense tornado. Many injuries and numerous fatalities reported - numbers unknown - and houses and businesses flattened.

AT 648 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TOINDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZEHAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WASLOCATED NEAR LAKIN...OR 6 MILES SOUTH OF POMEROY...MOVING EAST AT 65MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TOBANCROFT...POCA...HARTFORD CITY...CROSS LANES...SYRACUSE...LETART...NEW HAVEN...MOUNT ALTO...RACINE...CHESTER...LIBERTY...COTTAGEVILLE.. .EVANS...GIVEN...SISSONVILLE...RAVENSWOOD...KENNA. ..PORTLAND...FAIRPLAIN...RIPLEY...COAL FORK...FORKED RUN STATE PARK...STATTSMILLS...KENTUCK...REEDSVILLE...SANDYVILLE...PINCH ...BELLEVILLE...ELKVIEW...GAY...HARMONY...LEROY...CLENDENIN...WAL TON...ROCKPORT...GANDEEVILLE...PEEWEE...MORRISTOWN...REEDY...MINER ALWELLS...SPENCER...DAVISVILLE...LOONEYVILLE...LUCILLE...PALESTINE... ELIZABETH...GREENCASTLE...CHERRY...WALKER AND FREEPORT

THIS WILL IMPACT THE FOLLOWING INTERSTATES...I-77 BETWEEN MILEMARKERS 102 AND 171 IN WEST VIRGINIA...I-79 BETWEEN MILE MARKERS 1AND 22.

TORNADIC SUPERCELL POTENTIAL WILL CONTINUE TO INCREASE THIS EVENING AND INTO THE EARLY OVERNIGHT HOURS ACROSS A LARGE PORTION OF AL AND WRN-NWRN GA. ASIDE FROM THE THREAT OF TORNADOES /POTENTIALLY SIGNIFICANT/...SUPERCELLS WILL ALSO POSE AN ACCOMPANYING DMGG STRAIGHT-LINE WINDS RISK.

23Z SURFACE ANALYSIS SHOWS A LARGE UNIMPEDED WARM/MOIST SECTOR ACROSS AL AND MOVING INTO WRN PARTS OF GA --AHEAD OF A DRYLINE OVER NWRN MS. 3 HR CHANGE IN SURFACE TEMP/DEWPOINT SHOW A DECREASE OF 2-7 DEG F AND A 2 DEG F INCREASE...RESPECTIVELY. THE FORECAST CONTINUED TREND IN LOWERING SURFACE SPREADS AND LESS SUBSTANTIAL BOUNDARY LAYER MIXING WILL SEEMINGLY PROVE MORE FAVORABLE FOR LOW LEVEL MESOCYCLONES. SLIGHT IMPROVEMENTS IN THE LOW LEVEL THERMODYNAMIC PROFILE WILL ACCOMPANY A STRENGTHENING IN THE LLJ /40-55 KTS/ FROM SWRN AND W-CNTRL AL NEWD INTO NRN GA IN THE NEXT FEW HOURS. THIS WILL SET THE STAGE FOR A POSSIBLE NOCTURNAL TORNADO EPISODE FROM CNTRL AND E-CNTRL AL NEWD INTO N-CNTRL GA. THIS SCENARIO IS AT LEAST SUPPORTED TO A CERTAIN EXTENT BY THE LATEST STORM-SCALE MODEL ENSEMBLE /SSEO/. AS SUCH...SCATTERED DISCRETE SUPERCELLS WILL POSE AN ATTENDANT ISOLD TORNADO THREAT --WITH PERHAPS A FEW STRONG TORNADOES WITH THE MORE INTENSE SUPERCELLS.

Based on the videos, WHAS meteorologists estimate some of them as borderline EF4 or EF5, but that's unofficial.

S. Alabama is flaring up with isolated tornadoes, maybe peaking. At least it's not as bad as Tennessee or Kentucky, as far as anything obvious...

Good chance that the West Liberty tornado was an EF5. Already reports of multiple deaths and injures. Thats all I have heard. For all we know West Liberty may no longer exist. Prayers go out to them all.

TORNADIC SUPERCELL POTENTIAL WILL CONTINUE TO INCREASE THIS EVENING AND INTO THE EARLY OVERNIGHT HOURS ACROSS A LARGE PORTION OF AL AND WRN-NWRN GA. ASIDE FROM THE THREAT OF TORNADOES /POTENTIALLY SIGNIFICANT/...SUPERCELLS WILL ALSO POSE AN ACCOMPANYING DMGG STRAIGHT-LINE WINDS RISK.

23Z SURFACE ANALYSIS SHOWS A LARGE UNIMPEDED WARM/MOIST SECTOR ACROSS AL AND MOVING INTO WRN PARTS OF GA --AHEAD OF A DRYLINE OVER NWRN MS. 3 HR CHANGE IN SURFACE TEMP/DEWPOINT SHOW A DECREASE OF 2-7 DEG F AND A 2 DEG F INCREASE...RESPECTIVELY. THE FORECAST CONTINUED TREND IN LOWERING SURFACE SPREADS AND LESS SUBSTANTIAL BOUNDARY LAYER MIXING WILL SEEMINGLY PROVE MORE FAVORABLE FOR LOW LEVEL MESOCYCLONES. SLIGHT IMPROVEMENTS IN THE LOW LEVEL THERMODYNAMIC PROFILE WILL ACCOMPANY A STRENGTHENING IN THE LLJ /40-55 KTS/ FROM SWRN AND W-CNTRL AL NEWD INTO NRN GA IN THE NEXT FEW HOURS. THIS WILL SET THE STAGE FOR A POSSIBLE NOCTURNAL TORNADO EPISODE FROM CNTRL AND E-CNTRL AL NEWD INTO N-CNTRL GA. THIS SCENARIO IS AT LEAST SUPPORTED TO A CERTAIN EXTENT BY THE LATEST STORM-SCALE MODEL ENSEMBLE /SSEO/. AS SUCH...SCATTERED DISCRETE SUPERCELLS WILL POSE AN ATTENDANT ISOLD TORNADO THREAT --WITH PERHAPS A FEW STRONG TORNADOES WITH THE MORE INTENSE SUPERCELLS.

..SMITH.. 03/02/2012

I'm starting to get a little scared. Going to have to stay up all night. Live in North Fulton GA/Roswell.

TORNADIC SUPERCELL POTENTIAL WILL CONTINUE TO INCREASE THIS EVENING AND INTO THE EARLY OVERNIGHT HOURS ACROSS A LARGE PORTION OF AL AND WRN-NWRN GA. ASIDE FROM THE THREAT OF TORNADOES /POTENTIALLY SIGNIFICANT/...SUPERCELLS WILL ALSO POSE AN ACCOMPANYING DMGG STRAIGHT-LINE WINDS RISK.

23Z SURFACE ANALYSIS SHOWS A LARGE UNIMPEDED WARM/MOIST SECTOR ACROSS AL AND MOVING INTO WRN PARTS OF GA --AHEAD OF A DRYLINE OVER NWRN MS. 3 HR CHANGE IN SURFACE TEMP/DEWPOINT SHOW A DECREASE OF 2-7 DEG F AND A 2 DEG F INCREASE...RESPECTIVELY. THE FORECAST CONTINUED TREND IN LOWERING SURFACE SPREADS AND LESS SUBSTANTIAL BOUNDARY LAYER MIXING WILL SEEMINGLY PROVE MORE FAVORABLE FOR LOW LEVEL MESOCYCLONES. SLIGHT IMPROVEMENTS IN THE LOW LEVEL THERMODYNAMIC PROFILE WILL ACCOMPANY A STRENGTHENING IN THE LLJ /40-55 KTS/ FROM SWRN AND W-CNTRL AL NEWD INTO NRN GA IN THE NEXT FEW HOURS. THIS WILL SET THE STAGE FOR A POSSIBLE NOCTURNAL TORNADO EPISODE FROM CNTRL AND E-CNTRL AL NEWD INTO N-CNTRL GA. THIS SCENARIO IS AT LEAST SUPPORTED TO A CERTAIN EXTENT BY THE LATEST STORM-SCALE MODEL ENSEMBLE /SSEO/. AS SUCH...SCATTERED DISCRETE SUPERCELLS WILL POSE AN ATTENDANT ISOLD TORNADO THREAT --WITH PERHAPS A FEW STRONG TORNADOES WITH THE MORE INTENSE SUPERCELLS.